I don't think Umaira Ahmed is a very humorous writer. Mehreen has done some light hearted plays too. In this play Javeria's character is a bit light hearted but I don't think the play itself requires a hero's comedic sidekick or a paan chewing funny grandma.
you don't need to create a comic or exaggerated chartacter to create humor.you can create it in a normal conversation or by taking situations from every day life.like shoaib mansoor did in ABC.